1. Field of the Invention
The present invention relates to electrical connectors for flat cables.
2. Description of the Related Art
Japanese Patent No. 3047862 discloses a connector of this type. As shown in FIGS. 5(A) and 5(B), this connector includes a plurality of terminals 51 arranged in the direction perpendicular to the drawing sheet. The terminal 51 has upper and lower arms 52 and 53 which are connected by a linking section 54, forming a substantially H-shape. The lower arm 53 is in contact with the bottom wall 56 of a housing 55, with one of its ends 57 engaged with the housing 55. The other end forms a connection section 58 outside the housing 55. The upper arm 52 is made flexible and has a contact portion 52A at one end to cooperate with the contact portion 53A of the lower arm 53 for holding a flat cable P between them for contact. See FIG. 5(B). At the other end, it has a corner portion 52B to receive a force from a movable member 59 when the movable member 59 rotates from the position of FIG. 5(A) to the position of FIG. 5(B). Consequently, the contact portion 52A is pressed onto the flat cable P.
The movable member 59 has a corner portion 59A to serve as a cam for the corner portion 52B. When the corner portion 59A moves past the corner portion 52B, it makes a click sound and presses the upper arm 52 to keep the contact pressure of the contact portion 52A.
There is a demand for a low-profile connector of this type. Also, it is required to provide a sufficient click sound or sensation to indicate that the movable member is brought to such a position that a satisfactory contact pressure is provided between the terminal and the flat cable.
However, the above connector fails to meet both the requirements at the same time.
The degree of click sensation is large when the angle between the two straight sections of the corner portion 52B is large because the contact position with the movable member changes quickly. However, if the angle is too large, no low-profile connector is provided. Also, when the movable member 59 moves past the corner portion 52B, the upward pressure is lowered too quickly to provide satisfactory contact pressure between the contact portion 52A and the flat cable. In other words, when the satisfactory contact pressure is maintained, the angle of the corner portion is too small to provide a satisfactory click sensation.